Grid winding machine



Oct. 19, 1965 G. J. DRIES ETAL 3,212,725

GRID WINDING MACHINE Filed July 2, 1962 2 Sheets-Sheet 1 S E S S E N T WOct. 19, 1965 G. J. DRlES-ETAL 3,212,725

GRID WINDING MACHINE Filed July 2, 1962 2 Sheets-Sheet 2 United StatesPatent 3,212,725 GRID WINDING MACH- ENE Gerald J. Dries, SouthDansville, and Goliardo Miale,

Bath, N.Y., assignors to Westinghouse Electric Corporation, EastPittsburgh, Pa., a corporation of Pennsylvania Filed July 2, 1962, Ser.No. 206,895 5 Claims. (Cl. 2429) This invention relates to themanufacture of grid electrodes for electron discharge devices and, moreparticularly, to a method and apparatus for making these gridelectrodes.

In the manufacture of grid electrodes, it is customary to provide aplurality of spaced support members around which a wire is wound toprovide the grid laterals. The wire which forms the grid laterals issupplied from some suitable source, usually a spool, and is directedonto the support members to form the grid laterals. The manner in whichthe grid laterals are formed is customarily achieved by directing thegrid wire through a suitable guide and providing between this guide andthe spaced support members both relative rotational and longitudinalmovements. Perhaps the most usual way of winding a grid electrode is tohave a stationary wire source and winding guide, and providing bothrotational and longitudinal movements of the support members. However,it is also quite usual to provide that the support members arestationary and that the winding head is provided with both rotationaland longitudinal motion with respect to the support members. It is alsopossible that combinations of these movements be utilized.

Grid electrodes are commonly wound in strips; that is, several grids arewound successively and after being wound are separated to form theindividual electrodes. A grid is normally comprised of two areas,namely, the active area in which it is necessary to have grid lateralsand a leg portion in which there are no lateral wires. In order toconserve lateral wire and time in winding the grid electrode, it isdesirable that in the leg portion of the grid, the number of turns oflateral wire be held to a minimum, even to the point of not placingwires in this area. This conservation of wire and time is customarilyachieved by one of two methods. Either of these two methods may beutilized regardless of the manner in which the relative longitudinalmotion between the support rods and the winding guide is achieved. Thefirst of these methods provides that the winding is continuous but thatin the leg portion of the grid strip the rate of longitudinaladvancement is greatly increased so that the adjacent turns of gridlateral wire are spaced a greater distance apart. The second methodcustomarily used is to break the wire at the end of one active gridportion, shift the mechanism over the leg portion of the grid, andcommence winding with the next active grid portion. In either method,the demand upon the grid wire is subject to very rapid changes.

The continuously winding method is commonly used on frame grids; thatis, grids having a pair of spaced support rods and cross bars extendingbetween the support rods to hold them in their spaced relationship. Inthese cases, the wire customarily used is extremely fine and has,therefore, a very low tensile strength. Thus, when the demand upon thewire is suddenly increased by the greater spacing between adjacentturns, the wire often breaks. The break 3,2 12,725 Patented Oct. 1 9, 1965 method is commonly used on notch and peen type grids where the gridlaterals serve to maintain the support members in their spacedrelationship. In this latter method, the grid wire is often much heavierthan that used in the case of frame grids. However, upon the initiationof the Winding of a new grid, the demand on the wire rises at an almostinfinite rate from zero demand to full demand. Thus, even though thewire of this method is generally of greater size, this extremely rapidrise in demand can easily result in a breaking of the grid wire.

While various tensioning devices are known in the art whichsatisfactorly serve to adjust for fluctuations in the demand occasionedby the non-symmetry of the grid about its rotational axis, thesetensioning devices normally depend upon the change in tension of thewire to make the proper adjustment. Because the demand in theaboveillustrated cases changes so rapidly, conventional type oftensioning devices are not sufficiently responsive to adjust to thisextremely rapid change and the result is a broken grid wire.

It is, therefore, an object of this invention to provide an improvedgrid winding machine.

Another object is to provide improved tensioning means for use in themanufacture of grid electrodes.

A still further object is to provide improved means to compensate forsudden changes in demand for grid lateral wire in the manufacture ofgrids for use in electron discharge devices.

Stated briefly, the present invention provides that sudden changes indemand for grid lateral wire are anticipated. This anticipation permitsthe reduction of fluctuation in tension between the grid wire source andthe support members to provide a more constant tension between theelements. Thus, upon a sudden change in demand, the amount of wirenecessary to supply the demand is readily available without increasingthe tension upon the grid wire to limits which exceed the tensilestrength of the wire. By the utilization of the present invention, theability to rapidly wind grids and yet take advantage of a reduction inlateral wire in non-active grid areas is readily achievable.

Further objects and advantages of the invention will become apparent asthe following description proceeds and features of novelty whichcharacterize the invention will be pointed out in particularity in theclaims annexed to and forming a part of this specification.

For a better understanding of the invention, reference may be had to theaccompanying drawings, in which:

FIGURE 1 shows a diagrammatic front view of a grid machine embodying thepresent invention;

FIGS. 2A and 2B are diagrammatic views of, respectively, conventionaland frame grid strips illustrating the areas of the winding process inwhich the present invention is necessary;

FIG. 3 is a perspective view of the present invention in its preferredembodiment as applied to the winding of grids having no turns in the legportion; and

FIG. 4 is a perspective view of the present invention in its preferredembodiment as applied to the winding of grids having a very few turns inthe leg portion.

The invention comprises, in general, a system which takes the form of anattachment which can be easily added to a standard grid making machinesuch as a rotary grid lathe a illustrated in FIG. 1. With specificreference to FIG. 1, the machine is constructed similar to a lathe andcomprises a bed plate upon which is supported, at one end a head stock11 and at the other a tail stock 12. The head stock 11 includes a mainrotary spindle which is driven by suitable means 7. A tubular draw bar14 is provided at one end with a strip clamp 13 and on its other endwith a half nut or split nut 16. The half nut 16 may be opened andclosed by means of a handle 18. A lead screw 20 is provided having oneend rotatably mounted in the tail stock 12 and the other end positionedto engage the half nut 16.

The apparatus illustrated in FIG. 1 is designed to wind so-calledconventional grids by the notch and peen process. In this embodiment,each support member or side rod wire is automatically fed in acontinuous length from a spool 17 carried in a yoke 19 positioned on theouter end of a spindle 22. The support members 15 pass through channelsextending longitudinally through the spindle 22. A mandrel 21 is securedto the spindle 22 and groove are provided in the mandrel for the supportmembers 15. A notching wheel 26 and a peening wheel 25 are supported bysuitable means from the head stock 11 and are positioned adjacent themandrel 21. A grid wire 52 is directed onto the rotating support members15 from a suitable source, for example a spool 51. The grid lateral wire52 is supplied to the members 15 by means of the tensioning device ofthe present invention which is indicated generally at 50; whichtensioning device may be supported by the head stock 11.

The winding operation is started by securing the support members 15 bymeans of the clamp 13 on the draw bar 14. The half nut 16 is closed onthe lead screw so that as the draw bar 14 retreat due to the relativerotation between lead screw 20 and the draw bar 14, the support members15 are drawn through the channels in the head spindle 22 and alongopposite edges of the mandrel 21. The notching wheel 26 is mounted in aposition such that its periphery cuts a notch in each support member 15as that member is carried under the notching wheel 26 by the rotation ofthe mandrel 21. The grid wire 52 is then disposed within these notchesand is secured therein by a peening wheel as the support member 15 andgrid wire 52 are carried under the peening wheel 25 by the rotation ofthe mandrel 21. This operation is continued throughout that portion ofthe grid strip where it is desired to have grid laterals.

With reference now to FIG. 2A, there is shown a portion of a grid striphaving areas A which include grid turns and areas B which do not haveturns thereon. Areas A may be designated as the active grid portionswhile areas B are the respective leg portions of adjacent gridstructures. After the grid strip has been wound, the side rods 15 aresevered at approximately the midpoints between adjacent active areas Ato form individual grid electrodes as is customary in the art. A gridstrip such as is illustrated in FIG. 2A may be formed by breaking thegrid wire .at the end of a first active grid port-ion, advancing thesupport members 15 longitudinally to the point where it is desired totart the next active grid portion and at that time commencing once againthe winding of the grid laterals. The method and mechanism by which thisso-called wire break is achieved is more fully set forth in US. Patent3,121,448, filed November 4, 1960, entitled Grid ManufacturingApparatus, by Douglas G. Noiles et al., which application is assigned tothe assignee of the present invention. However, stated briefly, thispatent sets forth that having wound one active grid portion A, the gridwire is grasped between a pair of jaws to prevent further movement ofthe grid wire. Upon continued rotation of the support members 15, thegrid wire is caused to break at a point where last peened and themachine is then advanced to the next successive active grid portionwhere the grid wire i again picked up and wound around the supportmembers 15. By this method, no turns are wound in the leg portion B ofthe grid strip.

It may also be provided that the longitudinal movement of the members 15in the leg portion B is more rapid than the longitudinal movement whenthe active grid portion A is being wound.

While the heretofore described wire break method efifects a substantialsavings in time and grid wire certain difiiculties are prevalent in theoperation of the device in that the grid wire ha a tendency to break atthe initiation of a new active grid portion. In the winding ofconventional notch and peen grids, the wire diameters range customarilyfrom approximately 0.005 inch to 0.0006 inch. Winding tensions aredesired in the 250 to 50 gram range. Winding speeds, that is therotational speed of the support members, range up to 1500 revolutionsper minute. It is readily apparent that after the wire has been brokenits rate of feed i zero. Once the wire is attached to the rotatingsupport members at the initiation of .a new active grid portion it mustrise at an almost infinite rate to .a speed sufficient to supply thedemand of the support members which, as has been stated, may be rotatingat peeds up to 1500 rpm. Such a rapid acceleration in the grid wiresystem, because of the small diameters of the Wire used, often resultsin a breakage of the wire between the source and the support members.

A second feature tending to break the wire upon the initiation of a newactive grid portion results from the over-run of the wire sourceoccasioned by the inertia of the system when the wire break mechanism isoperated. This over-run produces some slack in the wire between thesource and the jaws which clamp the wire further complicating thebreaking problem in that when the wire is once more picked up to bewound upon the support members, the slack results in a snap in the wirewhich further increases its propensity to break. Some prior art systemshave attempted to reduce this slack by rotating the wire source in thereverse direction. While this system has some merit it often result inthe grid wire being pulled from the retaining jaws of the breakmechanism so that the wire cannot once again be automatically picked up.Thus, the machine must be re-threaded by hand.

With reference now to FIG. 3, there is shown the tensioning device ofthe present invention as it is applied to the winding of conventionalgrids by the notch and peen process and which may be incorporated withthe wire break system. The device includes a source of wire in the formof a spool 30 which is secured to a shaft 32 of a motor 34. The wire 52is taken from the top of the spool, looped around a pulley 38, broughtback once again around the spool 30, from the underneath side, and fromthe top of the spool taken to the support members 15. The pulley 38 isrotatably mounted on a resilient member 40 which may be secured to asuitable fixed reference for example the bed plate 10 of the device ofFIG. 1. Thus, the pulley 38 is provided not only with rotary motion butalso with an arcuate reciprocal motion towards and away from the spool30. Intermediate the spool 30 and the support members 15 are a pair ofblocks 42 which represent the gripper jaws of the Wire break system. Thejaws also act as a guide means for directing wire onto the supportmembers 15. The device as a whole is supported by a suitable housing 36which may be supported from the bed plate 10 and head stock 11 of thedevice of FIG. 1.

In the winding operation, the grid wire 52 is fixed to one of thesupport members 15 and the members 15 are then caused to rotate and movelongitudinally. These movements of the support members 15 draw wire fromthe spool which wire passes around the pulley 38 and from the pulley 38back around the spool 30 and then to the support members 15. The normaldirection of rotation of the spool 30 as, viewed in FIG. 3, is in thecounterclockwise direction. During the winding of the active gridportion A (FIG. 2A), the motor 34 is deactivated and acts as a spindlefor the spool 30. The

requisite tension on the grid wire 52 during the normal windingoperation is provided by any suitable friction or hysteresis tensioningdevice. In FIG. 3 this tensioning device is shown to be of africtionable nature and is illustrated by a resiliently mounted member45 which is in frictional contact with a wheel 44 which is also securedto the motor shaft 32.

After an active grid portion A has been wound, the wire break jaws 42clamp on the wire 52 and thus prevent the rotating members 15 fromdrawing additional wire from the spool 30. This results in a breakage ofthe wire at the support members 15. As the system as a whole has acertain amount of rotational inertia, the sudden stoppage of the wire 52results in some over-run of the system. If and when desirable, thisover-run can be reduced or eliminated by the addition of a suitablesecond brake on the motor spindle which is momentarily actuated at theinstant the wire breaks. This second brake and actuating means are notshown. However, in view of the nature in which the wire is wound, nearnormal winding tension is maintained in the wire between the spool andthe pulley 38 and the bulk of the reduction in tension is taken up inthe wire between the jaws 42 and the spool 30. This reduction in tensionis not harmful.

The critical time of tensioning, however, is when the lateral wire 52 ispicked up to start winding the next active grid portion A. At this timewire demand goes from zero to full speed in virtually zero time-the rateof change approaching infinity, No servo device, responsive to anincrease in tension of the lateral wire 52, is sufiiciently fast torespond to this high rate of change; and the forces occasioned by thisrapid rate of change may often be sufficient to break the wire 52.

In the present invention, however, there is connected to the spool 30 adriving means which is shown as a small electric motor 34. The motor 34is connected to a suitable source of voltage 48 through an adjustableimpedance 46 and a switch 47. The switch 4-7 may be actuated by the samemechanism which initiates the action of the wire break jaws 42 asdescribed in the previously mentioned US. Patent 3,121,448 and/ or therapid longitudinal advancement of the support members 15. This mechanismis customarily a rotatable cam mounted on the apparatus of FIG. 1. Anysuitable means, for example a cam follower linking the cam and theswitch 47 will serve to actuate the latter. The cam and cam followermechanism is illustrated as Item 8 and is described in US. Patent3,121,448. The direction of rotation of the motor 34 when energized isin the direction of unspooling. Thus, by utilizing the actuatingmechanism of the wire break jaws 42 to control the switch 47, and byadjusting the potential applied to the motor 34 through the impedance46, it is seen that this actuating mechanism may cause the energizationof the motor 34 an amount and for a proper period of time to overcomethe inertia of the spool by turning the spool in the direction of normalrotation, to compensate for the sudden increase in wire demand. Themotor 34 is energized at a time which is closely coincident with theinitiation of the winding of an active grid portion. A ready indicatonof the proper adjustment of time and amount of input torque of the motor34 is by observing the action of the pulley 38. When these parametersare properly adjusted the pulley 38 has very little arcuate motion onthe resilient member 40 thus indicating a nearly constant tension beingmaintained on the wire 52. If these parameters are improperly adjusted,the amount of arcuate motion of the pulley 38 will be considerable.

A second method of reducing the number of grid turns in the leg portionof the grid is illustrated in FIG. 2B. In FIG. 2B there is shown a gridstrip having a pair of spaced support members 15 which are held in theirspaced relationship by a plurality of cross members 23. As in the caseof FIG. 2A the active grid portion is designated as A and the legportion is designated as B. In this example, however, a very limitednumber of widely spaced turns are placed in the leg portion of the gridstrip. This wide spacing of grid turns in the leg portion is achieved byrapidly advancing the support members 15 with respect to the windinghead. The mechanism (herein designated as skip or skip turn) by whichthis is accomplished is more fully set forth in US. Patent No.3,029,844, filed May 22, 1959, entitled Grid Making Machine by WilliamH. Simmonds and which is assigned to the assignee of the presentinvention. Although this skip method of winding the leg turns will workequally well in the notch and peen process of conventional grids it isexplained with respect to frame grids where it finds a greaterapplication.

In the winding of frame type grids the lateral wires are normally heldonto the support rods by their own tension and the wires are of asmaller diameter than those usually found in grids of the conventionalnotch and peen process. A typical example of a frame grid would utilizewire in a diameter of approximately 0.0004 inch and winding would be ata rotational speed of about 700 r.p.m.

The embodiment of the present invention as it is applied to the windingin the skip turn process is shown in FIG. 4. In that figure, there isshown a source or spool 30 of wire 52 which is attached to a shaft 32 ofa motor 34. As in the embodiment of FIG. 3, the assembly of thisembodiment is supported by a housing 36. The rotational and longitudinalmovements of the support members 15 draw wire from the spool 30 so as tocause the spool 30 to rotate, as viewed in FIG. 4, in the clockwisedirection. After leaving the spool 30 the lateral wire 52 is caused topass over a rotating pulley 60, from the pulley 60 to a second pulley 62and from there through a guide member 64 onto the support members 15.The pulley 62 and the guide member 64 may be supported by a suitablemember 66 which is affixed to a fixed reference point such as the lathebed 10 (FIG. 1). The pulley 60 is rotatably supported on a resilientmember 68 which in turn is supported by the housing 36. A member 70limits the upward movement of the resilient member 68. Normal windingtension in the present embodiment is provided by a strap 71, of asuitable material such as canvas, which is passed around and infrictional engagement with a pulley 72 which may also be located on theshaft 32. One end of the strap 71 is connected to a spring 74 which inturn is connected to the resilient member 68 near the pulley 60. Theother end of the strap 71 is connected to a screw 76 which in turnpasses through a bracket 78. The screw 76 is provided with a wing nut 80at its upper portion to provide fine adjustment of the strap 71 on thepulley 72. The bracket 78 is supported by the housing 36 and meansincluding a screw 82 and slot 84 may be provided for coarse adjustmentof the tensioning means.

As the tension on the grid lateral wire 52 increases, pulley 60 iscaused to move in the downward direction which in turn reduces thepressure of the strap 71 on the pulley 72. Hence the frictionalrestraint on the rotation of the spool is lessened and the spool 30 ispermitted to more freely rotate to relieve the increased wire tension.Conversely, as the tension on the lateral wire 52 decreases the pulley60 moves in the upward direction and hence increases the amount oftension on the lateral wire 52. The device thus described is selfregulating and even through the lateral wire 52 is very thin this systemadequately compensates for variations in tensions occasioned by thewinding of the active grid portion Where the turns are evenly spaced orhave only a small variance. The above is old in the art.

However, once the grid strip reaches the end of an active grid portionand it is desired to wind the turns on the leg portion, which turns aremuch more greatly spaced apart, it is apparent that the demand for wirerapidly increases. As an illustration, normal distance'between adjacentgrid laterals in the active portion of the grid may be approximately0.0025 inch while the spacing between adjacent turns in the leg portionapproaches 0.25 inch. The sudden increase in wire demand occasioned bythe greater spacing often places stresses upon the lateral wire 52 forwhich the normal tensioning device just described cannot compensate.Although a Wire of this diameter normally has a breaking strength ofabout 30 grams, it has been found that measurable winding tensions above15 grams often produce Wire breakage, even in uniform pitch winding.

The active area of the frame grid is wound with tension produced only bythe tensioning device described. Here, as in the case of the embodimentof FIG. 3, the motor is not energized and serves as a spindle for thespool 30. At the time the support members 15 are rapidly advanced,resulting in a rapid increase in wire demand, the motor 34 is pulsedfrom a source 48 through the adjustable impedance 46 and the switch 47.Here again, as in the embodiment of FIG. 3, the voltage applied to themotor 34 may be adjusted by the impedance 46 and the duration of thepulse adjusted through the actuation of the switch 47. The mechanism,for example a rotating cam, which effects the rapid advancement of thesupport members 15 may be utilized to actuate the switch 47 as was donein the case of the previous embodiment. As before, the direction ofrotation of the motor is such to provide an unspooling of the wire (inFIG. 4 the motor runs to effect a clockwise motion of the spool 30). Aready indication of proper adjustment of time and amount of the torquesupplied by the motor 34 is easily discernible by observation of theaction of pulley 60. With the proper adjustment there is very littlemovement of the pulley 60 during the skip period thus indicating arelatively constant wire tension. That is, the pulley 60 is relativelystationary even though the skip mechanism is operated and the wiredemand is greatly increased.

It is thus seen that by the present invention there is provided animproved means for maintaining a grid lateral wire under the propertension between its source and the support members even though thedemand upon this supply varies between very great limits. By the presentinvention, there is provided a device which is readily adaptable tostandard grid making machines and which greatly facilitates the use ofvarious methods for conserving time and material in the grid makingprocess.

While there have been shown and described what are at present consideredto be the preferred embodiments of the invention, modifications theretowill readily occur to those skilled in the art. For example, theinvention is not limited to use in systems as have been described,namely, the wire break and skip turn mechanisms, but is equallyapplicable to any system in which there is a very rapid change in demandupon a strand such that there may be occasioned a breakage of thatstrand.

It is not desired, therefore, that the invention be limited to thespecific arrangements shown and described and it is intended to cover inthe appended claims all such mod ifications as fall within the truespirit and scope of the invention.

We claim as our invention:

1. A grid Winding machine comprising a spindle, a first means forrotating said spindle, a plurality of spaced support members held by androtated with said spindle, a second means for advancing said supportmembers longitudinally, a source of grid wire, a third means forsupplying said grid wire to said support members whereby upon saidrotative and longitudinal movements thereof said grid wire is drawn fromsaid source and is wound about said support members, said third meansincluding a fourth means for maintaining said wire under tension betweensaid grid wire source and said support members, a fifth meansoperatively associated with said first means to pause a periodicincrease in demand of said grid wire from said source of grid wire, anda sixth means independent of said fourth means for maintaining said wireunder tension and operatively associated with said fifth means forsupplementally drawing said grid wire from said source. l st 2. A gridwinding machine comprising a spindle, a first means for rotating saidspindle, a plurality of spaced support members held by and rotated withsaid spindle, a second means for advancing said support memberslongitudinally, a source of grid wire, a third means for supplying saidgrid wire to said support members whereby upon said rotative andlongitudinal movement thereof said grid wire is drawn from said sourceand is wound around said support members, said third means comprising afourth means for maintaining said wire under a predetermined tensionbetween said source and said support members, a fifth means operativelyassociated with said first means to cause a periodic increase in demandfor grid wire from said source, and a sixth means independent of saidfourth means and operatively associated with said fifth means forsupplementing the action of said support members in drawing said gridwire from said source in response to said periodic increase in demandfor said grid wire.

3. A grid winding machine comprising a spindle, a first means forrotating said spindle, a plurality of spaced I support members held byand rotated with said spindle,

a second means for advancing said support members longitudinally at afirst speed, a spool of grid wire, and a third means for supplying saidgrid wire to said support members wherein upon said rotative andlongitudinal movements of said support members wire is drawn from saidspool and wound about said support members, a fourth means operativelyassociated with said first means to cause a periodic increase in demandfor grid wire from said source, and a fifth means adapted to drive saidspool and operatively associated with said fourth means forsupplementing the action of said support members in removing wire fromsaid spool simultaneously with said periodic increase in demand.

4. A grid winding machine comprising a spindle, a first means forrotating said spindle, a plurality of spaced support members held by androtated with said spindle, a second means for advancing said supportmembers longitudinally, a spool of grid wire, a third means forsupplying said grid wire from said spool to said support members wherebyupon said rotative and longitudinal movements thereof said grid wire iswound around said support members, said third means comprising a fourthmeans for maintaining said grid wire under tension between said spooland said support members, a fifth means operatively associated with saidfirst means to cause a periodic increase in demand for grid wire fro-msaid spool, a motor means operatively associated with said fifth means,said spool adapted to be driven by said motor means in the direction ofunspooling simultaneously with said periodic increase in demand for saidgrid wire by said support members.

5. A grid winding machine comprising a spindle, a first means forrotating said spindle, a plurality of spaced support members held by androtated with said spindle, a second means for advancing said supportmembers longitudinally, a source of grid wire, a third means forsupplying said grid wire to said support members whereby upon saidrotative and longitudinal movements thereof said grid wire is woundaround said support members, said movements acting to draw wire fromsaid source, a fourth means operatively associated with said first meansto cause a periodic increase in demand for said grid wire from saidsource, a fifth means for maintaining said Wire under a uniform tensionbetween said source and said support member, motor means operativelyassociated with said source of grid wire, and a sixth means independentof said fifth means for maintaining said wire under tension 9 10operatively associated with said fourth means and said 2,959,367 11/60Kuba et a1. 242-9 motor means to supplement the action of said support2,981,491 4/61 Eans 24245 members in drawing wire from said sourcesimultaneously 3,029,844 4/ 62 Simmonds 14071.5 with said periodicincrease in demand of grid wire. 3,039,706 6/62 Toth et a1. 242--9 53,045,713 7/62 Cleven 140-715 References CIted y the Examiner 3,054,4309/62 Van T01 et al. 140 71.5

UNITED STATES PATENTS FOREIGN PATENTS 1,970,599 3/34 Franks 242 9 X 7 7Great B in. 2,006,819 7/35 Zschach 242-45 1 2 2 5 54 42 Hanna et aL 24245 O MERVIN STEIN, Primary Examiner- 2,566,848 9/51 Morton 24245HARRISON R. MOSELEY, Examiner.

3. A RIGID WINDING MACHINE COMPRISING A SPINDLE, A FIRST MEANS FORROTATING SAID SPINDLE, A PLURALITY OF SPACED SUPPORT MEMBERS HELD BY ANROTATED WITH SAID SPINDLE, A SECOND MEANS FOR ADVANCING SAID SUPPORTMEMBERS LONGITUDINALLY AT A FIRST SPEED, A SPOOL OF GRID WIRE, AND ATHRID MEANS FOR SUPPLYING SAID GRID WIRE TO SAID SUPPORT MEMBERS WHEREINUPON SAID ROTATIVE AND LONGITUDINAL MOVEMENTS OF SAID SUPPORT MEMBERSWIRE IS DRAWN FROM SAID SPOOL AND WOUND ABOUT SAID SUPPORT MEMBERS, AFOURTH MEANS OPERATIVELY ASSOCIATED WITH SAID FIRST MEANS TO CAUSE APERIODIC INCREASE IN DEMAND FOR GRID WIRE FROM SAID SOURCE, AND A FIFTHMEANS ADAPTED TO DRIVE SAID SPOOL AND OPERATIVELY ASSOCAITED WITH SAIDFOURTH MEANS FOR SUPPLEMENTING THE ACTION OF SAID SUPPORT MEMBERS INREMOVING WIRE FROM SAID SPOOL SIMULTANEOUSLY WITH SAID PERIODIC INCREASEIN DEMAND.